I have the same problem. THe other night I got up, went to the elevator, had it come to my floor (6th 0f 6) and I put a piece of card board to stop it all night. I finally got some sleep!
Then,I had the bldg. mgr get a technician to come over today and check it out, and I'm going to ask the rental board if I can have my rent lowered. I'll let you what happens.